1. Field of the Invention
This invention relates to metal roof deck assemblies and more particularly to acoustical roof panel assemblies having structural integrity, efficient sound absorbing properties and superior thermal insulation values.
2. Description of the Prior Art
Convention centers, arenas, office buildings and other major structures normally must provide for the economical handling of noise control. One way to accomplish this is to form metal roof panels into acoustical ceiling roof panel assemblies to meet the necessary noise reduction coefficients.
Conventional acoustical roof decking consists of a metal panel which forms a balanced section over the ceiling supports. By balanced section, it is meant that the panels include alternating flats and ribs of approximately the sam width. In order not to materially reduce the load bearing capacity of the panel, perforations ar placed in the sidewalls of the ribs and not on the flat surfaces which form the ceiling and which extend between ribs. Fiberglass units are then laid in the ribs to complete the acoustical ceiling.
At one time, Fenestra Incorporated produced an acoustical roof in which the width of the flats substantially exceeded the width of the ribs and perforations occurred along the flats. This product included a sound absorbing element formed of a formed arched pad, one inch thick, molded from a one-pound density, extra fine glass fiber. The sound absorbing element was placed between the ribs and a ply of roofing felt was laid dry over the tops of the exposed ribs and sound absorbing element to form a vapor seal and asphalt stop. However, because the insulation element had an arched configuration, special equipment had to be designed and the insulation custom made. This substantially increased the cost of the product so as to be noncompetitive with the conventional prior art acoustical deck. In general, it is also known to use spacers to separate a sound absorbing pad from the face of the ceiling, see U.S. Pat. Nos. 2,293,351; 2,271,929; 2,148,496; 2,112,631 and 1,899,403.
A need remains for an acoustical metal roof deck panel assembly providing adequate structural support and efficient sound absorbing properties which can be manufactured with existing conventional techniques. The need also exists for an acoustical panel which can be finally painted after installation without getting substantial amounts of paint on the insulation member itself.